bsd man page for environ

ENVIRON(7)						 Miscellaneous Information Manual						ENVIRON(7)

NAME
       environ - user environment

SYNOPSIS
       extern char **environ;

DESCRIPTION
       An  array  of  strings called the `environment' is made available by execve(2) when a process begins.  By convention these strings have the
       form `name=value'.  The following names are used by various commands:

       PATH    The sequence of directory prefixes that sh, time, nice(1), etc., apply in searching for a file known by an  incomplete  path  name.
	       The prefixes are separated by `:'.  Login(1) sets PATH=:/usr/ucb:/bin:/usr/bin.

       HOME    A user's login directory, set by login(1) from the password file passwd(5).

       TERM    The  kind  of  terminal for which output is to be prepared.  This information is used by commands, such as nroff or plot(1G), which
	       may exploit special terminal capabilities.  See /etc/termcap (termcap(5)) for a list of terminal types.

       SHELL   The file name of the users login shell.

       TERMCAP The string describing the terminal in TERM, or the name of the termcap file, see termcap(5),termcap(3X).

       EXINIT  A startup list of commands read by ex(1), edit(1), and vi(1).

       USER    The login name of the user.

       PRINTER The name of the default printer to be used by lpr(1), lpq(1), and lprm(1).

       Further names may be placed in the environment by the export command and `name=value' arguments in sh(1), or by the setenv command  if  you
       use  csh(1).   Arguments  may  also be placed in the environment at the point of an execve(2).  It is unwise to conflict with certain sh(1)
       variables that are frequently exported by `.profile' files: MAIL, PS1, PS2, IFS.

SEE ALSO
       csh(1), ex(1), login(1), sh(1), execve(2), system(3), termcap(3X), termcap(5)

4.2 Berkeley Distribution					   May 20, 1985 							ENVIRON(7)